采用自制的介孔分子筛Ti/W-MCM-41催化乳酸与正戊醇的酯化反应,合成了乳酸正戊酯;利用红外光谱仪分析了催化剂的化学特征,考察了分子筛的WO3质量分数、催化剂用量、醇酸物质的量比、反应时间、催化剂重复使用性能等因素对目标产物酯化率的影响.结果表明.在nsi∶nTi=30∶1,WO3质量分数10％,550℃下焙烧6h条件下制得的催化剂具有良好的催化性能;其催化合成乳酸正戊酯适宜的反应条件为:0.2mol乳酸,催化剂用量0 5 g,n(正戊醇)∶n(乳酸)=1.6∶1,反应时间100 min,酯化率可达94.4％.该催化剂使用7次酯化率仍可达86.6％.%A novel catalyst, Ti-based W-containing MCM-41 (Ti/W-MCM-41) mesoporous mo-lecular sieve was prepared. The mesoporous molecular sieve was employed to catalyze the es-terification reaction of lactic acid and n-pentanol yielding namyl lactate. The effects of various parameters such as mass ratio of WO; , catalyst dosage, molar ratio of alcohol to acid, reaction time and reusability of the catalyst on the esterification rate were investigated. Results indicate that the mesoporous molecular sieve obtained at a nSi : nTi= 30 : 1, WO3 mass ratio of 10% af-ter calcination at 550℃ for 6 h possesses good catalytic performance. Relevant molecular sieve catalyst can be well used to catalyze the esterification reaction of lactic acid and n-pentanol yielding namyl lactate under the optimized reaction condition of lactic acid 0. 2 mol, alcohol to acid molar ratio of 1. 6 : 1, mass of catalyst 0. 5 g, and reaction time of 100 min; resultant es-terification rate is as much as 94. 4%. Besides, the esterificalioii rate is still over 86. 6% after the catalyst is reused for 7 times.
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